mail.ZCDN.RU has no NS records.
NS records for this zone are defined at ZCDN.RU.
NS records for this zone are defined at ZCDN.RU.
Question and response
Question
dig mail.ZCDN.RU. NS
Answer
The response has no answer records.
Authority
zcdn.ru. 10800 SOA ns2.zcdn.ru. adm.zcdn.ru. 2025092618 14400 7200 2419200 10800
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0